Hi Ollie

This may be an interesting effect, but it is not a compressor.


The attack and delaytimes are a direct "portamento" on the envelope
voltage of the original signal. They are NOT attacktimes of a separate
envelope circuit. You may find a suggestion here:
http://fa.utfs.org/diy/a100/A100_compressor.jpg


The signals envelope voltage is inverted in the A175 (then fed through
the VCS A159 which I will neglect at the moment(*)), then the A170 slew
limiter adds the slew rate on the fast changing original envelope, which
controls the VCA.


Florian

(*)The VCS decides, with the threshold of the gate out when the signals
envelope voltage starts to become valid - also this is not what a real
compressor is working like).